I just came here to talk about it. This isn't just about Janne Da Arc, but about his situation in general and reading it I'm not sure if he will come back ever again, also not as ABC. It seems he indirectly knew that, when he started ABC, Janne Da Arc was kind of over for him, because he didn't write a single song for Janne Da Arc since he decided to start ABC. I guess he felt he grew out of it while he became an adult. Then he started to notice that something wasn't right during the rehearsal of Live Erect tour and after two operations and trying to get better, he isn't able to get his voice out as strong as before. He also mentions that he can't sing the songs he wrote as he would like to anymore.
All in all it sounds as if he really wants to come back as ABC, but his condition won't let him.
I hope I'm reading too much into all of this, but personally I wouldn't be surprised if in a few months there will be an announcement that he won't come back anymore.